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A semiclassical theory of the Ehrenfest-time dependence of quantum transport in ballistic quantum dots

Piet W. Brouwer·Saar Rahav
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Abstract

We present a trajectory-based semiclassical calculation of the Ehrenfest-time dependence of the weak localization correction and the universal conductance fluctuations of a ballistic quantum dot with ideal point contacts. While the weak localization correction is proportional to exp(-tau_E/tau_D), where tau_E and tau_D are the dot's Ehrenfest time and dwell time, respectively, the variance of the conductance is found to be independent of tau_E. The latter is in agreement with numerical simulations of the quantum kicked rotator [Tworzydlo et al., Phys. Rev. B 69, 165318 (2004) and Jacquod and Sukhorukov, Phys. Rev. Lett. 92, 116801 (2004)].

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Piet W. Brouwer, Saar Rahav. 2006-03-30. A semiclassical theory of the Ehrenfest-time dependence of quantum transport in ballistic quantum dots. https://doi.org/10.1103/physrevb.74.075322

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